Air diffuser



C. DAVIES June 10, 1969 AIR DIFFUSER I Filed Feb. 25. 1968 :3 Rm. H T NN 1 R E 0 Vi mm n M A C United States Patent Qfice 3,448,675 PatentedJune 10, 1969 3,448,675 AIR DIFFUSER Charles Davies, 265 Coligni Ave.,New Rochelle, N.Y. 10801 Filed Feb. 23, 1968, Ser. No. 707,806 Int. Cl.F24f 7 02 US. CI. 98-40 8 Claims ABSTRACT OF THE DISCLOSURE Twoconcentric cylindrical walls define an annular air flow passage betweenthem. An electric light housed within inner wall. Air inlet opening nearupper endsof walls. Flange projects radially outwardly from lower end ofinner wall, defining annular air outlet opening between flange edge andouter wall. Annular baflle projects radially inwardly from outer walland is slidable vertically along outer wall, and may be positioned toalternatively block air, or cause horizontal or vertical flow of airfrom outlet.

This invention relates to air diffusers, and more particularly to such adiffuser which introduces air into a room through a continuous slot,usually situated in the ceiling of the room, surrounding a source ofillumination.

It is an object of the invention to provide an improved diffuserstructure which permits the direction of an air pattern flowing into aroom, as well as its volume, to be controlled in a very simple manner.

Another object of the invention is to provide such an air diffuser whichis admirably adapted to be combined with a source of illumination forthe room.

To accomplish these and other objectives, the invention provides innerand outer concentric walls of, preferably, circular cross-sectiondefining an annular flow passage between them. The diameter of the innerwall is large enough to accommodate an electric light installation. Anair inlet opening is provided near the top of the annular passage, andan annular flange projects radially outwardly from the lower end of theinner wall, thereby defining an annular outlet opening between the freeedge of the flange and the outer wall. An annular baifle projectsradially inwardly from the outer wall and is vertically adjustable sothat in cooperation with the flange it can control the direction andvolume of air flowing from the diffuser.

Additional objects and features of the invention will be apparent fromthe following description in which reference is made to the accompanyingdrawings.

In the drawings:

FIG. 1 is a longitudinal cross-sectional view through a diffuseraccording to this invention showing the baflle in one position ofadjustment;

FIG. 2 is a view similar to FIG. 1 showing the baflle in anotherposition of adjustment; and

FIG. 3 is transverse cross-sectional view taken on line 3-3 of FIG. 2. j

The air diffuser chosen for illustration comprises a pair ofconcentrically arranged cylindrical walls 10 and 11, which may be formedof any suitable material such as sheet metal. The diameter of the outerwall 11 is substantially greater than that of theinner wall so as toprovide an air flow passage 12 between the walls. The air flow passage12 is continuous, when viewed in crosssection (see FIG. 3), and in thepresent example is annular in shape. A circular top wall 13, having anupstanding lip secured by any suitable means to the upper margin of theouter wall 11, serves as a closure at the upper ends of the walls 10 and11. Near its upper end, the outer wall 11 is furnished with an air inletopening 14 adapted to communicate with a duct 15 for channeling air tobe diffused into the flow passage 12. At its lower end, the outer wall11 is formed with an outwardly projecting flange 16 by means of whichthe diffuser may be secured, by suitable fasteners, to a supportstructure 17, such as a ceiling.

The inner wall 10 presents a flange 20 at its upper end secured to lowerface of the top wall 13. A circular flan-ge 21 projects radiallyoutwardly from the lower end of the inner wall 10, the radial dimensionof the flange 21 being smaller than the spacing between the walls 10 and11 so as to define an annular outlet opening 22 'between the free edgeof the flange 21 and the lower edge of the outer wall 11.

For the purpose of controlling the direction and volume of air flow fromthe outlet 22, an annular baflle or damper 23 is adjustably arrangedwithin the flow passage 12. The baflle 23 has an L-shaped cross-section,its vertical arm 24 extending adjacent and parallel to the outer wall11, and its horizontal arm 25 extending radially inwardly from the outerwall. The radial dimension of the arm 25 is illustrated as being greaterthan the corresponding dimension of the outlet 22. However, it isessential only that the radial dimension of the arm 25 be great enoughso that when the arm 25 is brought into adjacence with the flange 21 (asshown in dot-dash lines in FIG. 1), the outlet 22 will be closed.

The external diameter of the bafie 23 is slightly smaller than theinternal diameter of the outer wall 11 so that the baffle may beadjusted vertically within the flow passage 12. A number of leaf springs26 are fastened at circumferentially spaced intervals about the arm 24of the baffle, and project upwardly therefrom, the upper ends of thesprings being suitably deformed to frictionally engage the inner surfaceof the outer wall 11. In this way, the springs 26 serve to maintain thebaffle 23 in any desired position of adjustment. Adjustment of thebaffle is effected, in the present example, by a manually manipulabletool 29 having a hook-shaped end adapted to cooperate with twodiametrically arranged loops 30 projecting downwardly from the arm 25 ofthe baflle. Obviously, however, other means of baflle adjustment may beemployed.

With the bafile 23 located relatively far from the flange 21, as shownin solid lines in FIG. 1, air flowing through the duct 15 and into theflow passage 12 will follow the path of the arrows in FIG. 1 and enterthe room through the outlet 22 in a direction substantiallyperpendicular to the ceiling 17. This mode of introduction of air into aroom might be desirable, for example, if the air is warm and is intendedto heat the room.

By moving the bafl'le 23 down closer to the flange 21, as shown in FIG.2, the air flowing through the duct 15 and flow passage 12 isconstrained to follow the path of the arrows in FIG. 2 and enter theroom through the outlet 22 in a substantially horizontal direction,i.e., parallel to the ceiling 17. This type of flow pattern may bedesired when the air introduced is intended to cool the room.

If the baflie 23 is moved even closer to the flange 21 than as shown inFIG. 2, the volume of air entering the room will of course be reduced.Finally, if the baffle is brought into engagement with the flange 21, asshown in dot-dash lines in FIG. 1, all air flow through the outlet 22 isblocked.

The air diffuser of this invention is admirably adapted to incorporate asource of illumination within it so as to produce a combined airdiffuser and recessed electric lighting fixture of the type commonlyreferred to as a high hat. In the illustrative embodiment, aconventional electric light socket 31 is secured to the lower face ofthe top wall 13 within the inner wall 10. The socket is supplied withelectric current via conductors 32, and threadably accommodates anelectric light bulb 33. If desired,

ngers i 3 a light diffusing element (not shown) may be mounted on theinner wall 10 beneaththe bulb 33.

It will be appreciated that a device according to this invention offersseveral advantages, among which are the following: an air diffuser andlight source may be installed simultaneously with little more effortthan is required to'install an air diffuser alone; and by means of asingle movable part, adjustable to a number of different positions, airmaybe directed into a room perpendicular or parallel to the ceiling, itsvolume may be varied, or air flow may be cut off entirely.

The invention has been shown and described in preferred form only, andby Way of example, and many variations may be made in the inventionwhich will still be comprised within its spirit. For example, ratherthan the walls 10 and 11 being cylindrical, they could have a square,rectangular, or any other useful cross-sectional shape. It isunderstood, therefore, that the invention is not limited to any specificform or embodiment except insofar as such limitations are included inthe appended claims.

What is claimed is:

' 1. An air diffuser comprising a pair of coaxial walls spaced apart todefine an air flow passage between them, said air flow passage beingcontinuous in cross-section, an air inlet opening near the upper end ofone of said walls, a flange projecting outwardly from the inner wallnear the lower end of the latter, said flange having a width smallerthan the spacing between said walls thereby defining an air outletsurrounding the free edge of said flange, and a single continuous bafllewithin said air flow passage and completely surrounding the inner wall,said baffle being located adjacent to the inner surface of the outerWall and projecting inwardly therefrom, said baflie having a width atleast as large as the corresponding dimension of the air outlet, andsaid baffle being slidable vertically along the inner surface of theouter wall so that it may be optionally positioned (a) spaced relativelyfar from said flange so that air will flow from said outlet in asubstantially vertical direction, (b) spaced relatively close to saidflange so that air flowing from said outlet may be varied mint rad amassamma horizontal 66inponent of movement, or (0) in engagement with saidflange so that air flow is blocked, positioning of only said singlebaffle as described serving to vary both direction and volume of airflow.

2. An air diffuser as defined in claim 1 wherein each of said walls hasa circular, cross-sectional shape, and said baflie is annular. E

33. air diffuser as defined in claim 2 wherein said walls are in theform of concentric cylinders;

4. An air diffuser as defined in claim 1 including means for supportinga source of illumination within the inner wall, saidinner 'wallservingas the sole housing for said source of illumination. v

. 5. An air diffuser. as definedin claim 4wherein said means includes anelectric socket for threadably accepting an electric lightbulb. Y 1

6. An air diffuser as defined in claim 1 wherein said baffle has anL-shaped cross-section, the vertical arm of baflie extending parallel toand slidable along theouter of said concentric walls.

7.. An air diffuser as defined in claim 6 including a spring carried bysaid bafile and frictionally engaging one of said walls.

8. An installation including an air diffuser as defined in claim 1,meansfor securing said diffuser to'the ceiling of a room, andmeans forchannelingair to be diffused to I said inlet opening.

References Cited UNITED STATES PATENTS 8/1935 Riddell 98-37 3,302,550 2/1967 Thomson 98-40 3,310,672 3/1967 Bursell 98-40 X 33220332 11/1965Straub 9840 3,406,623 10/1968 Lambert 98-40 WILLIAM E. WAYNER, PrimaryExaminer.

Us. c1. X.R-.

